Tonight on Dateline, I hear a female scream and two gunshots. A heartbreaking case and now for the first time the full story.

My friend is laying on the bathroom floor and there's blood everywhere.

Everybody just loved Mo.

I am here with the fabulous Mo Wilson.

You are like ready.

I'm ready.

Exclusive new video and the inside details you haven't heard.

I'm going to be Betty yesterday. you haven't heard. He's the last person she saw.

There had been a previous short romantic history.

His girlfriend didn't know that he went out with Mariah the night before.

Did you consider them both to be persons of interest?

Yes.

The only problem is she's gone.

It's a really good place for people to hide out. The only problem is she's gone.

It's a really good place for people to hide out. She asked about it no job.

This could be the person that we're looking for.

I see a call that an inmate is escaping.

I was dumbstrugg.

Who hated Mariah so much that they wanted her dead?

She was a champion cyclist, but even she couldn't outrace her killer. I'm Lester Holt and

this is Dateline. Here's Keith Morrison with the night time stopped. It was too late for all their frantic haste.

The young woman lying on the bathroom floor in the tiny above the garage apartment was long beyond saving.

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